Rufus Stone, New Forest, Saturday, 26th October 2013

Neil Sanderson lead a Wessex Bryology Group meeting at Rufus Stone on the 26th October, this concentrated on bryophytes and one very significant lichen find was made. A total of 16 people attended.

The meeting was in one of the richest and well known bryophyte sites in the New Forest; the area around the Rufus Stone. To the east is “Canterton Glen”, a sheltered valley cutting to to the clay scarp with old growth Sessile Oak – Beech wood on the slopes and Pedunclate Oak – Beech stand below. This is the richest wood for oceanic bryophytes in the Forest and is also the first recorded core area in the New Forest for the internationally rare old growth dependent moss Zygodon forsteri. To the west between the old growth Beech - Oak woods are open areas with bryophyte rich short grazed Molinia – Cirsium dissectum grassland. West of this is Coalmere Gutter another sheltered rich valley woodland.

The aim of the meeting was a general familiarisation with the bryophyte flora, rather than detailed species listing. However, we did have a brief to look out for the very rare moss Zygodon forsteri EN (NR/S41), which was being surveyed in the New Forest by Fed Rumsey for Natural England. It is a species of wound tracks on ancient Beeches, which is only known in the UK from the New Forest, Burnham Beeches and Epping Forest. We also had our sights on the oceanic liverwort Plagiochila bifaria, recorded in 1992 in Canterton Glen; the only Hampshire record.

First we headed east into the Canterton Glen woods. At the cathedral Beeches by the car park, which seems to have been the original core area for Zygodon forsteri, we found our first Zygodon forsteri tree:

RS01 (SU27140 12513): Zygodon forsteri on wound track at base of old maiden Beech 40x 40cm with dominant protenema and leafy plants frequent. Also in second root knot hole.

RS01 Zygodon forsteri

After this we headed up into the head of the valley. Lichen interest noted on passing:

RS02 (SU27155 12423): Beech with Phyllopsora rosei NT (NS/IR) and Porina borreri Nb (NS) and a rich moss flora with Neckera complanata and Homalia trichomanoides.

RS03 (SU27195 12396): Beech with Thelopsis rubella.

We then got up on to an ancient landslip area on the clay scarp in shady Beech – Holly – Oak wood. This is one of the best oceanic liverwort sites in the Forest, with hot spots on landslip banks and the sides of small incised streams. The oceanic liverwort Saccogyna viticulosa began to occur widely on banks but was also found on damp fallen logs just beyond the core area. The magnificent oceanic liverwort Bazzania trilobata also occurred along the banks of small streams cutting down through the scarp.

RS04 (SU27168 12371) & RS05 (SU27283 12330): Bazzania trilobata on banks. Above 05 was the lichen Leptogium lichenoides on a collapsed Beech. There were several base rich old Beeches looking suitable for Plagiochila bifaria in the general area where it was found previously, but unfortunately none was found. The area is a bit dark and could do with more Holly pollarding.

A shaded pond created in a rotational landslip feature was dominated by a green Bog Moss. This was clearly a Sphagnum recurvum group taxa but I could not make out what. Sharon Pilkington identified it as Sphagnum angustifolium, which was the one New Forest Sphagnum I had not found; so a good find.

We then stopped for lunch but a heavy shower had us sheltering under an ancient twisted Beech. Followed by lunch in a glade.

Bazzania trilobata & sheltering from the rain

I then lead the party down into the wood, aiming for an area where a large Zygodon forsteri colony was extant in the early 2000s. On the way there at RS06 (SU27269 12386): some fertile Porina hibernica (NT, NS/IR/S42), a rare southern oceanic lichen, was noted Beech.

Further on, winding around the clumps of dense Holly I walked around a promising looking Beech I was startled I find my self looking at a huge Zygodon forsteri colony reaching up 4m up into the tree:

RS07 (SU27286 12553): massive strip of Zygodon forsteri protenema 4m x 50m in wound track originating from wound on old maiden Beech, with locally dominant patches of leafy Zygodon plants.

High up this Beech was a colony of Polypody fern that had the outline of Polypodium cambricum, a rare epiphyte in the New Forest that is confined to base rich bark and is an honoree member of the Lobarion community here.

We proved not to be to far from the open track east from the car park where there was an big Zygodon forsteri colony a few years ago. We failed to locate this, but found three more and a colony of the lichen wound track specialist Bacidia incompta (VU, NS/S41). The first Zygodon forsteri was found by Andy Cross, who went on to find another:

RS08 (SU27288 12602): Zygodon forsteri a few cushions in an area of 5cm across on old maiden Beech.

RS09 (SU27263 12591): Bacidia incompta in wound track on Beech

RS10 (SU27244 12580): Zygodon forsteri in wound track on base of old maiden Beech trunk, 50 x 40cm with leafy plants abundant with numerous old capsules.

Near by were Strigula taylorii Nb (NS/IR) (new to wood) and Opegrapha vermicellifera (new to wood) on Beech

RS11 (SU27216 12576): Zygodon forsteri below knot hole on prone Beech

Nearby were the lichens Mycoporum lacteum (NT, NS) (new to wood) on Holly and Agonimia octospora NT (NS/IR) on Beech.

Finally back at the car park at RS12 (SU27095 12563) a known colony of the beautiful fungi Hericium erinaceus inside hollow fallen Beech log was pointed out. In the first part of the meeting we had had remarkable tour of rare Beech specialists, with an astonish haul of five new Zygodon forsteri trees in one day.

A tour of rare Beech specialists

We the worked over the lawn to west, the eastern section had base rich flushes with a selection of calcicole bryophytes, including Scorpidium cossonii. I recorded the limited terricolous lichen assemblage found on raised heathy hummocks within the short grazed Rhos Pasture in SU2612:

Cladonia furcata subsp. furcata
Cladonia squamosa var. subsquamosa (the heathland form with wide flaring cups)
Cladonia portentosa
Cladonia floerkeana
Cladonia cryptochlorophaea
Cladonia diversa

Then passing through a belt of pasture woodland separating two areas of lawn, my eye was caught by a big leafy lichen on a sweeping Beech branch. The distinctive greasy shine, the general shape and the small white dots on the upper surface (punctiform pseudocyphellae) suggested Cetrelia olivetorum s. lat. and the UV + white fluorescence from the sorediate margins and no rhizines visible on the lower surface confirmed this. This was an exciting find; it was new to Stricknage Wood and previous there have been only two records from the New Forest and it has not seen since the early 1990s. It is a species in serious decline though out England and Wales, even in the far west.

The big thallus were also the biggest thalli of Cetrelia olivetorum s. lat. I had ever seen, much bigger than any I had seen in the west. The UV + white fluorescence meant that this could only be either the rare chemical-species Cetrelia chichitae (UV + white & KC + red) or the widespread Cetrelia cetrarioides (UV + bright white, KC –). I forgot to do the spot tests but the UV fluorescence was so bright it could only be from perlatolic acid so this was Cetrelia cetrarioides. Previously tested Cetrelia olivetorum s. lat. from the New Forest have also proved to be this chemical-species.

Cetrelia cetrarioides on a Beech branch

Further on, the lawn became more acidic and we found the declining heathland moss Hypnum imponens (NS) and I had a go at trying to refund the small plants of the upland moss Breutelia chrysocoma in there only known lowland site but gave up. It was still doing well in 2009 and is probably still there but needs time to find. We then reached Coalmere Gutter and located the oceanc moss Hyocomium armoricum, which is abundant along the banks of this stream, but unknown beyond in Hampshire.

Finally on the way back, a bank under a Holly on the edge of a track at RS14 (SU26337 12749) had a large spread off the lichen Trapeliopsis pseudogranulosa with apothecia was found; apparently the first fertile material from Britain. Further on Baeomyces rufus was recorded on the track bank.

Trapeliopsis pseudogranulosa with apothecia

The lichen species accorded on passing are listed on the species list. Download the KMZ file to view route and waymarks in Google Earth, or view as picture by clicking on link below.